The level of automation in industrial robots today is astonishing. 5-axis and 6-axis robots have so many joints and can still achieve precise transmission of motion and commands. Their various parts work together closely to complete complex tasks, which makes one wonder about their transmission systems and the structure of their joints.
Joints are one of the most important basic components of industrial robots and the core component of motion: precision reducers. This is a precision power transmission mechanism that uses a gear speed converter to reduce the motor's rotational speed to the desired speed while obtaining a larger torque, thereby reducing the rotational speed and increasing the torque.
The speed reduction transmission at the robot joints requires a short transmission chain, small size, high power, light weight, and easy control. At the same time, for industrial robots with medium to high loads, sufficient rigidity, rotational accuracy, and motion accuracy stability are also required.
Currently, there are only a few manufacturers worldwide capable of producing large-scale, reliable precision reducers. The vast majority of the market share is held by Japanese companies: Nabtesco's RV reducers account for approximately 60%, Harmonica's harmonic reducers for approximately 15%, and Sumitomo Heavy Industries (whose market share was not found). Their dominance is particularly pronounced in the robotics field.
▲Disassembling the internal structure of the precision reducer
Nabtesco was formed by the merger of two Japanese companies: Teijin Seiki and Nabtesco (which produced Japan's first automatic door in 1956). As manufacturers of motion control systems and components, both companies possessed advanced core technologies in their respective business areas and controlled a significant market share.
As the world's largest manufacturer of precision cycloidal pinwheel reducers, Nabtesco produces high-performance reducers, hollow shaft reducers, as well as single-axis servo actuators and controllers.
The precision equipment it produces has high torque, high rigidity and high resistance to overload impact loads, while also having high precision and very low backlash. It is widely used in industrial automation fields such as satellites, radar antennas, industrial robots, semiconductors and welding technology.
Reviewed by: Huang Fei
